(a) Technical Field
The present disclosure relates to a battery system for a vehicle, more particularly, to a high voltage-low voltage integrated battery system integrating a high voltage battery system used to provide driving power with a low voltage battery system for providing power to an electronic load, etc. of the vehicle.
(b) Description of the Related Art
Generally, an eco-friendly vehicle (such as a hybrid vehicle, electronic vehicle, fuel cell vehicle, etc.) having an electric motor for providing driving power to the wheels has a high voltage battery to provide energy of high voltage for the electric motor. In particular, high voltage means a voltage relatively higher than a voltage (generally, a range of 11 to 14 V) of a battery provided for starting an engine-driven vehicle or for supplying power to electronic loads.
Therefore, the eco-friendly vehicle generally has a high voltage battery for operating the electric motor and a low voltage battery for power supply to electronic loads separately. Managing individual power systems for separate high and low voltage batteries results in systems of enlarged size, and thus reduced efficiency.
To address this problem, utilizing a single battery assembly composed of several cells or modules, a conventional high voltage-low voltage integrated system in which parts of several battery modules that make up a high voltage battery are used for low-voltage power supply has been proposed.
However, the conventional high voltage-low voltage integrated system is problematic in that there is an imbalance in states of charge between several modules included in the single battery assembly, and thus efficiency or robustness of the system is degraded and operation becomes unstable.
The foregoing is intended merely to aid in the understanding of the background of the present disclosure, and is not intended to mean that the present disclosure falls within the purview of the related art that is already known to those skilled in the art.